Daonella

Daonella are typical bivalve molluscs from the Middle Triassic period (247-237 million years). Their thin, flat shells were reinforced with radiating ribs that, beside their circular to sub-triangular shell outline, characterize the species. D. lommeli is one of the largest and most widespread species. As it is often found in rocks deposited in the open sea, it is presumed that it lived afloat the water thanks to its thin, wide shell.